General
The viewer shows lightning-data from the Blitzortung-network [BO] and/or a single Boltek Stormtracker [BOL] depending on what the station has available. Blitzortung data has good accuracy (because of GPS) while Boltek Stormtracker have lesser accuracy because it is a single receiver. Both systems updates in realtime, Blitzortung in a radius of 250 km of the station and Boltek usually in a radius of 600 km. Blitzortung data covers whole Europe and the data outside the 250 km radius are updated once a minute.

Rainradars are updated every 15 minutes with varying delay.

Blitzortung
Blitzortung.org is a private network of lightning tracker stations with more than 1000 trackers in Europe. They catch the electromagnetic signals of strikes. Together with the time stamp the position of a strike can be calculated out of the signals (TOA - time of arrival method). You will find more information on the main site of the project: www.blitzortung.org.
Accuracy of Blitzortung is quite good and is usually lower than 1 kilometer. This is equal to commercial strike detection companies and metoffices.
To participate you have to get your own relatively inexpensive receiver. With that, you can participate in the network and you will get access to all strike data